--%>

Problem on work of compression

A diesel engine operates devoid of a spark plug by using the high-temperature gas produced throughout the compression stage to ignite the fuel. During a typical compression, pure air that is originally at 21 °C and 0.95 bar is reversibly and adiabatically compressed to 1/20 of its original(actual) volume by the piston, as shown in the figure below.

a) If air is assumed to obey the ideal gas equation of state, find out the pressure and temperature in the cylinder at the end of the compression. The constant-pressure heat capacity of air varies with temperature and is given by

Cp/R = 3.3 + 6x10-4

b) What is the work of compression in J/mol of air?

c) Is the ideal gas law a good approximation in this case? Why?

2455_ideal gas law.jpg

   Related Questions in Mechanical Engineering

  • Q : Define Product Design Specification

    Product Design Specification: Once the basic idea for a product has been made, the next step is to create a product design specification, or PDS. This document must be as comprehensive and as detailed as possible as it forms the basis of all the work

  • Q : Problem related to the value of the

    Water flows via a pipe of about 300 mm diameter at the rate of 66 L/s. Evaluate the value of the manometer reading, ‘h’. The Specific gravity of manometer liquid is taken as 0.8.  

  • Q : Problem on mechanical efficiency of the

    The oil pump is drawing 25 kW of electric power while pumping oil with ρ = 860 kg/m3 at a rate of 0.1 m3/s. The inlet and outlet diameters of the pipe are of 8 cm and 12 cm, respectively. When the pressure rise of oil in the pump is measured to be 250 k

  • Q : Problem on steam turbine 1) A steam

    1) A steam turbine takes in saturated steam at 300oc and outputs steam at 4 bar. When the efficiency of the turbine is 65%, Evaluate: a.  The final composition (vapor vs. liquid) of outgoing steam.b.  The

  • Q : Difference between mill and mill-drill

    Difference between mill and mill-drill: Nowadays numerous manufactures are combining machines; a mill-drill is one of such. This is a combination of a drill and a mill, a mill eliminates stock from material (genera

  • Q : Lubricating oil in turbines Except the

    Except the lubrication, explain the other two functions of the lubricating oil in some of the turbines?

  • Q : Static and Dynamic load What are Static

    What are Static and Dynamic load and what are their significant dynamic effects?

  • Q : Define spinning jenny Spinning jenny:

    Spinning jenny: It is a multi-spool spinning wheel. It was invented in the year 1764 by James Hargreaves in Stanhill, close to Blackburn, Lancashire in the north west of England (though Thomas Highs is another candidate recognized as inventor).

  • Q : Modal Combination Rules What are the

    What are the Modal Combination Rules in order to determine the peak value of the total response?

  • Q : Measuring the Temperature in Wet Bulb

    Explain phenomenon to measure the Temperature in Wet Bulb Thermometer?